Golf clubs and golf club heads having a removable mass ring

ABSTRACT

A golf club head includes a wood type golf club head body. Further, the golf club head may include a mass ring that engages with the golf club head body. The mass ring may increase a moment of inertia of the golf club head body when the mass ring engages the golf club head body. The mass ring includes an opening in the center of the mass ring. Further, a portion of the exterior of club head body may extend through the opening in the center of mass ring. The mass ring may form a portion of the exterior of the golf club head body when the mass ring is engaged with the golf club head body. The mass ring may be engaged with the sole portion of the golf club head body. The mass ring may be engaged with the rear portion the golf club head body.

RELATED APPLICATION DATA

This application is a continuation of U.S. patent application Ser. No. 12/571,586, filed Oct. 1, 2009, the disclosure of which is hereby incorporated by reference.

FIELD OF THE INVENTION

The present disclosure relates to golf clubs and golf club heads. Particular example aspects of this disclosure relate to golf clubs and golf club heads having a removable mass ring.

BACKGROUND

Golf is enjoyed by a wide variety of players—players of different genders and dramatically different ages and/or skill levels. Golf is somewhat unique in the sporting world in that such diverse collections of players can play together in golf events, even in direct competition with one another (e.g., using handicapped scoring, different tee boxes, in team formats, etc.), and still enjoy the golf outing or competition. These factors, together with the increased availability of golf programming on television (e.g., golf tournaments, golf news, golf history, and/or other golf programming) and the rise of well known golf superstars, at least in part, have increased golf's popularity in recent years, both in the United States and across the world.

Golfers at all skill levels seek to improve their performance, lower their golf scores, and reach that next performance “level.” Manufacturers of all types of golf equipment have responded to these demands, and in recent years, the industry has witnessed dramatic changes and improvements in golf equipment. For example, a wide range of different golf ball models now are available, with balls designed to complement specific swing speeds and/or other player characteristics or preferences, e.g., with some balls designed to fly farther and/or straighter; some designed to provide higher or flatter trajectories; some designed to provide more spin, control, and/or feel (particularly around the greens); some designed for faster or slower swing speeds; etc. A host of swing and/or teaching aids also are available on the market that promise to help lower one's golf scores.

Being the sole instrument that sets a golf ball in motion during play, golf clubs also have been the subject of much technological research and advancement in recent years. For example, the market has seen dramatic changes and improvements in putter designs, golf club head designs, shafts, and grips in recent years. Additionally, other technological advancements have been made in an effort to better match the various elements and/or characteristics of the golf club and characteristics of a golf ball to a particular user's swing features or characteristics (e.g., club fitting technology, ball launch angle measurement technology, ball spin rates, etc.).

While the industry has witnessed dramatic changes and improvements to golf equipment in recent years, there is room in the art for further advances in golf club technology.

SUMMARY

The following presents a general summary of aspects of the disclosure in order to provide a basic understanding and various aspects of the disclosure. This summary is not intended to limit the scope of the disclosure in any way, but it simply provides a general overview and context for the more detailed description that follows.

Aspects of this invention relate to golf club heads comprising a wood type golf club head body. Further, the golf club head may include a mass ring configured to be engaged with the golf club head body. The mass ring may be configured to increase a moment of inertia of the golf club head body when the mass ring engages the golf club head body. The mass ring includes an opening in the center of the mass ring. Further, a portion of the exterior of club head body may extend through the opening in the center of mass ring. The mass ring may be configured to form a portion of the exterior of the golf club head body when the mass ring is engaged with the golf club head body. The mass ring may be configured to be engaged with the sole portion the golf club head body. The mass ring may be configured to be engaged with the rear portion the golf club head body.

Additional aspects of this disclosure relate to wood-type golf club structures that include golf club heads, e.g., of the types described above. Such golf club structures further may include one or more of: a shaft member attached to the club head (optionally via a separate hosel member or a hosel member provided as an integral part of one or more of the club head or shaft); a grip or handle member attached to the shaft member; weighting members; etc.

Still additional aspects of this disclosure relate to methods for producing golf club heads and golf club structures, e.g., of the types described above. Such methods may include, for example: (a) providing a golf club head of the various types described above, e.g., by manufacturing or otherwise constructing the golf club head body, by obtaining the golf club head body from another source, etc.; and (b) engaging a shaft member with the golf club head body at a separate hosel member or a hosel member provided as an integral part of one or more of the club head or shaft.

Methods according to examples of this disclosure may include additional steps, such as engaging a grip member with the shaft member; engaging a mass ring with the club head body; etc. Other steps also may be included in these methods, such as club head body finishing steps, etc.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is illustrated by way of example and not limited in the accompanying figures, in which like reference numerals indicate similar elements throughout, and in which:

FIG. 1 is an illustrative embodiment of a golf club according to at least some aspects of this disclosure;

FIGS. 2A-2D generally illustrate features of golf club head structures according to at least some examples of this disclosure;

FIG. 3 is an illustrative embodiment of a mass ring according to at least some aspects of this disclosure;

FIG. 4 is an illustrative embodiment of a mass ring according to at least some aspects of this disclosure being engaged with a golf club head body according to at least some aspects of this disclosure;

FIG. 5 is an illustrative embodiment of a mass ring according to at least some aspects of this disclosure;

FIG. 6 is an illustrative embodiment of a mass ring according to at least some aspects of this disclosure being engaged with a golf club head body according to at least some aspects of this disclosure; and

FIGS. 7A-7C illustratively depict aspects of a method of fitting a golf club and associated devices.

The reader is advised that the various parts shown in these drawings are not necessarily drawn to scale.

DETAILED DESCRIPTION

The following description and the accompanying figures disclose features of golf club heads and golf clubs in accordance with examples of the present disclosure.

General Description of Example Golf Club Heads, Golf Clubs, and Methods in Accordance with this Invention

Even with all the improvements in golf club technology in recent years golfers continue to lose valuable distance on golf shots wherein the golf ball is struck off center of the ball striking face. Therefore, aspects of the disclosure are directed to golf club heads that include an interchangeable mass ring which can aid a golfer in minimizing the distance lost when the golfer strikes the golf ball with a portion of the ball striking face that is off center.

Generally, a golfer attempts to strike a golf ball with the center of the ball striking face of the golf club head. By striking the golf ball with the center portion of the golf club head body, the golf ball generally travels a maximum distance possible relative to the velocity of the swing. However, if a golf ball is struck with a portion of the golf club head body that is off center, then the golf ball usually does not travel as far as if it was struck in the center portion (provided, of course, that the swing velocity is the same). This is because, when a mis-hit occurs (e.g., when the golf ball is struck with the toe end or heel end of the golf club head body), the golf ball head will twist and, as a result, exhaust energy that would have been imparted to the golf ball. In order to limit the loss of distance that occurs from a mis-hit, the amount that the golf club head twists during a mis-hit should be limited as much as possible.

Moment of Inertia (MOI) is a property of physics that refers to the changing of an object's angular motion about an axis. As applied to a golf club head, the MOI usually refers to the club head's ability to resist twisting about a known axis (usually the plane of the ball striking face). The higher the MOI the more resistant the club head will be to twisting, while, conversely, the lower the MOI the more readily the club head will succumb to twisting. Therefore, during a mis-hit, a golf club head with a high MOI will twist less and, therefore, less energy will be exhausted as a result of the twist. Hence, that energy may be imparted to the golf ball to cause the golf ball to travel farther. Essentially, the higher the MOI of the golf club head, the less distance will be lost on a mis-hit (i.e., the club head has more “forgiveness”). Therefore, it would be beneficial for a golf club head to have a relatively high MOI, so that the golf club head would be more “forgiving” on mis-hits.

One illustrative method of increasing the MOI of a golf club head is to move as much of the mass of the golf club head as possible to the perimeter of the golf club head. For a wood-type golf club head, the interior of the golf club head is usually hollow and the golf club head body comprises walls that are generally extremely thin (e.g., in the range of a couple millimeters). Therefore, in order to provide more mass at the perimeter of the golf club head, masses or weights may be engaged with the portions of the golf club head, such as the walls of the golf club head. For example, according to aspects of this disclosure, an interchangeable mass ring can be engaged with one or more portions of the golf club head body. Engaging the interchangeable mass ring with such portions of the club head distributes more of the mass of the golf club head towards the edge of the golf club head body which can increase the MOI of the golf club head. As described above, this can provide a greater resistance to twisting and, hence, provide greater forgiveness upon a mis-hit.

According to particular example aspects of this disclosure, the interchangeable mass ring may be positioned on a sole portion of the golf club head. This positioning redistributes the mass of the golf club head body so that more mass is in the sole edge of the golf club head and, therefore, the above described advantages can be achieved. Further, such a configuration may help a golfer achieve a higher trajectory. A common problem that many golfers experience, especially those just learning to play, is not being able to reliably get the ball in the air or achieving a desired trajectory. Positioning the interchangeable mass ring towards the sole of the golf club head can distribute more mass of the golf club head towards the sole which keeps more of the weight of the golf club head body low. This positioning can aid the golfer in getting the ball airborne upon striking the ball with the club head resulting in a higher trajectory.

According to further aspects of this disclosure, the interchangeable mass ring may be positioned on a rear portion of the golf club head. This positioning can redistribute the mass of the golf club head body so that more mass is in the rear edge of the golf club head and, therefore, the above described advantages are achieved. Further, such a configuration may help a golfer achieve a higher trajectory. Positioning the interchangeable mass ring towards the rear of the golf club head can distribute more mass of the golf club head towards the rear which keeps more of the weight of the golf club head body rearward. This positioning can aid the golfer in getting the ball airborne upon striking the ball with the club head resulting in a higher trajectory.

Aspects of this disclosure relate to wood-type golf club heads. Wood-type golf club heads according to at least some example aspects of this disclosure may include: (a) a wood-type golf club head body; (b) a ball striking face portion (including a ball striking face plate integrally formed with the ball striking face portion or attached to a frame member such that the face plate and frame portion together constitute the overall ball striking face portion); (c) a rear portion opposite the ball striking face; (d) a toe end portion; (e) a heel end portion; (f) a sole portion; and (g) a top or crown portion. The golf club head body may include an interchangeable mass ring. The club head body itself also may be constructed in any suitable or desired manner and/or from any suitable or desired materials without departing from this disclosure, including from conventional materials and/or in conventional manners known and used in the art.

Wide varieties of overall club head constructions are possible without departing from this disclosure. For example, if desired, some or all of the various individual parts of the club head body may be made from multiple pieces that are connected together (e.g., by adhesives or cements; by welding, soldering, brazing, or other fusing techniques; by mechanical connectors; etc.). The various parts (e.g., crown portion, sole portion, ball striking face portion, rear portion, toe portion, heel portion, body ribbon members, etc.) may be made from any desired materials and combinations of different materials, including materials that are conventionally known and used in the art, such as metal materials, including lightweight metal materials (e.g., titanium, titanium alloys, aluminum, aluminum alloys, magnesium, magnesium alloys, etc., composite materials, polymer materials, etc.). The club head body and/or its various parts may be made by forging, casting, molding, and/or using other techniques and processes, including techniques and processes that are conventional and known in the art.

For golf club structures according to this disclosure, the overall wood-type golf club structure may include a hosel region, a shaft member received in and/or inserted into and/or through the hosel region, and a grip or handle member attached to the shaft member. Optionally, if desired, the external hosel region may be eliminated and the shaft member may be directly inserted into and/or otherwise attached to the head member (e.g., through an opening provided in the top of the club head, through an internal hosel member (e.g., provided within an interior chamber defined by the club head), etc.). The hosel member may be integrally formed as part of the club head structure, or it may be separately formed and engaged therewith (e.g., by adhesives or cements; by welding, brazing, soldering, or other fusing techniques; by mechanical connectors; etc.). Conventional hosels and their inclusion in a wood-type club head structure may be used without departing from this disclosure.

The shaft member may be received in, engaged with, and/or attached to the club head in any suitable or desired manner, including in conventional manners known and used in the art, without departing from the disclosure. As more specific examples, the shaft member may be engaged with the club head via a hosel member and/or directly to the club head structure, e.g., via adhesives, cements, welding, soldering, mechanical connectors (such as threads, retaining elements, or the like), etc.; through a shaft-receiving sleeve or element extending into the club head body; etc. If desired, the shaft may be connected to the head in a releasable manner using mechanical connectors to allow easy interchange of one shaft for another.

The shaft member also may be made from any suitable or desired materials, including conventional materials known and used in the art, such as graphite based materials, composite or other non-metal materials, steel materials (including stainless steel), aluminum materials, other metal alloy materials, polymeric materials, combinations of various materials, and the like. Also, the grip or handle member may be attached to, engaged with, and/or extend from the shaft member in any suitable or desired manner, including in conventional manners known and used in the art, e.g., using adhesives or cements; via welding, soldering, brazing, or the like; via mechanical connectors (such as threads, retaining elements, etc.); etc. As another example, if desired, the grip or handle member may be integrally formed as a unitary, one-piece construction with the shaft member. Additionally, any desired grip or handle member materials may be used without departing from this disclosure, including, for example: rubber materials, leather materials, rubber or other materials including cord or other fabric material embedded therein, polymeric materials, cork materials, and the like.

Still other additional aspects of this disclosure relate to methods for producing wood-type golf club heads and wood-type golf club structures in accordance with examples of this disclosure. Such methods may include, for example, one or more of the following steps in any desired order and/or combinations: (a) providing a wood-type golf club head body and/or a golf club head of the various types described above (including any or all of the various structures, features, and/or arrangements described above), e.g., by manufacturing or otherwise constructing the golf club head body or the golf club head, by obtaining it from a third party source, etc.; (b) engaging a shaft member with the golf club head; (c) engaging a grip member with the shaft member; etc.

Given the general description of various example aspects of the disclosure provided above, more detailed descriptions of various specific examples of golf clubs and golf club head structures according to the disclosure are provided below.

Detailed Description of Example Golf Club Heads, Golf Club Structures, and Methods

The following discussion and accompanying figures describe various example golf clubs and golf club head structures in accordance with the present disclosure. When the same reference number appears in more than one drawing, that reference number is used consistently in this specification and the drawings to refer to the same or similar parts throughout.

An illustrative embodiment according to one or more aspects of the disclosure is shown in FIG. 1. FIG. 1 shows a golf club 100 at the address position which includes a wood-type golf club head body 102 in accordance with aspects of this disclosure and a shaft 106 and grip 107 engaged with the wood-type golf club head 102. According to some aspects of the disclosure, the dimensions of the club head body 102 may include a volume between 100-500 cubic centimeters (e.g., 460 cubic centimeters) and a mass between 75 and 250 grams (e.g., 200 grams). Further, according to aspects of this disclosure, the interior of the golf club head body 102 may be substantially hollow.

FIG. 2A illustrates a top view of an example of a wood-type golf club head body 102 according to aspects of this disclosure which includes a ball striking face portion 108, a rear portion 110 opposite the ball striking face, a crown (or top) portion 112, a sole portion 114, a toe end portion 116 and a heel end portion 118. In this specification, various features and aspects of the invention are defined based on geometry and locations with respect to a golf club head. As used in this specification and as illustrated with respect to FIG. 2A, the location of the “geometric center” 101 of a wood type golf club head 102 is determined in the following manner, which is consistent with the manner in which various club head dimensions are determined in Appendix II of The 2008-2009 Rules of Golf, as promulgated by the United States Golf Association (“U.S.G.A.”), which rules are entirely incorporated herein by reference. First, with the golf club head 102 oriented at its designed lie angle (the lie angle of its specifications, e.g., 60°), the outermost points P of the heel, toe, face, and rear of the club head 102 are determined. If the outermost point of the heel is not clearly defined (e.g., due to the club head's hosel, etc.), then the outermost point of the heel is deemed to be the location on the heel at 0.875 inches (22.23 mm) above the horizontal plane on which the club head is lying, in the same manner as the heel location is determined under The Rules of Golf mentioned above. Vertical projections along the outermost points P of the front, toe, rear, and heel (shown as “tangents” in the overhead view of FIG. 2) enclose the club head 102 within a rectangle or square structure, as shown in FIG. 2A (all angles being right angles). Then, a first diagonal line is drawn from the front heel corner to the rear toe corner of the rectangle or square structure (labeled “Front Heel to Rear Toe Diagonal” in FIG. 2A), and a second diagonal line is drawn from the front of the toe corner to the rear heel corner of the rectangle or square structure (labeled “Front Toe to Rear Heel Diagonal” in FIG. 2A). The intersection of these two diagonals D is deemed to be the “geometric center” 101 of the club head 102 as that term is used in this specification.

If necessary to provide a frame of reference, the front vertical projection or tangent line will be oriented square to the club head target line or direction at the outermost point P of the face surface, and then the heel and toe projections or tangents may be provided (at their outermost points) perpendicular to the front projection or tangent and the rear projection or tangent may be provided (at its outermost point) parallel to the front projection or tangent. An XY “coordinate axis” may be defined for the club head 102 by drawing a first coordinate axis (the Y-axis) in the front-to-rear direction perpendicular to the front and rear tangents through the geometric center 101 of the club head 102 and by drawing a second coordinate axis (the X-axis) in the heel-to-toe direction perpendicular to the first coordinate axis (and perpendicular to the heel and toe tangents) through the geometric center 101 of the club head body 102.

As shown in FIG. 2B, the “heel side” of the club head, as used in this specification, is defined as everything toward the heel 118 from the front-to-back Y coordinate axis. The “toe side” of the club head, as used in this specification, is defined as everything toward the toe 116 from the front-to-back Y coordinate axis. The “front side” of the club head, as used in this specification, is defined as everything forward of the heel-to-toe X coordinate axis. The “rear side” of the club head, as used in this specification, is defined as everything rearward of the heel-to-toe X coordinate axis.

As shown in FIG. 2C, the “rear heel side” of the club head, as used in this specification, is everything toward the rear side and heel side from the front heel to rear toe diagonal. The “rear toe side” of the club head, as used in this specification, is everything toward the rear side and toe side from the front toe to rear heel diagonal. The “front heel side” of the club head, as used in this specification, is everything toward the front side and heel side from the front toe to rear heel diagonal. The “front toe side” of the club head, as used in this specification, is everything toward the front side and toe side from the front heel to rear toe diagonal. The “heel edge” of the club head body is the edge surface along the heel side between the front heel to rear toe diagonal and the front toe to rear heel diagonal. The “toe edge” of the club head body is the edge surface along the toe side between the front heel to rear toe diagonal and the front toe to rear heel diagonal. The “rear edge” of the club head body is the edge surface along the rear side between the front heel to rear toe diagonal and the front toe to rear heel diagonal. The “front edge” of the club head body is the edge surface along the front side between the front heel to rear toe diagonal and the front toe to rear heel diagonal. Something located “proximate to” one of these edges, as used in this specification in this context, unless otherwise noted, means within 0.75 inches of the relevant edge.

As shown in FIG. 2D, the “rear heel quadrant,” “rear toe quadrant,” “front toe quadrant,” and “front heel quadrant” are defined using the geometric center 101 and the XY coordinate axes as described above.

While illustrated in FIGS. 2A through 2D on a relatively square shaped wood-type club head, these same definitions apply to more traditionally shaped wood-type golf club heads (e.g., as seen in FIGS. 1 and 3-7).

The “crown portion” of a golf club head is defined as that portion of the golf club head top surface that is visible looking directly downward on the club head when the golf club head body 102 oriented at its designed lie angle (the lie angle of its specifications, e.g., 60°). The “sole portion” of a golf club head is defined as that portion of the golf club head bottom surface that is visible looking directly upward on the club head when the golf club head body 102 oriented at its designed lie angle (the lie angle of its specifications, e.g., 60°). The topmost point of the club head crown portion and the bottommost point of the club head sole portion can be found by locating horizontal projections along the crown portion and the sole portion, respectively, with the club oriented as described above.

According to aspects of the disclosure, the golf club head body 102 may include a removable and interchangeable mass ring 201 which is configured to be engaged with the golf club head body 102. FIG. 3 is an illustrative embodiment of an interchangeable mass ring 201. As seen in FIG. 3, the mass ring 201 may be generally circular or oval shaped. However, the mass ring 201 could be formed in various other geometric shapes as well (e.g., square, rectangular, triangular, etc.). Of course, the ring shape of mass ring 201 will provide an opening in the center of the mass ring 201.

According to aspects of the disclosure, the interchangeable mass ring 201 may be configured to be engaged with the exterior of the golf club head body 102. For example, the mass ring 201 may be configured to form a portion of the exterior of the golf club head body 102 when the mass ring 201 is engaged with the golf club head body 102. According to one aspect of the disclosure, the interchangeable mass ring 201 may be configured to be engaged with the sole portion 114 the golf club head body 102 at an exterior of the sole portion 114. Further, according to some aspects of the disclosure, the exterior of the sole portion 114 may include a groove 114 a for receiving the mass ring 201. For example, FIG. 4 is an illustrative embodiment of such a golf club head 102 and mass ring 201 according to aspects of the disclosure. As seen in FIG. 4, the golf club head body 102 has a sole portion 114 with a groove 114 a according to aspects of this disclosure. As seen in FIG. 4, the groove 114 a may be a “cut-out” of the sole portion 114. In other words, when the club 100 is at the address position (see e.g., FIG. 1), the groove 114 a may recede upwards from an outer surface of the sole portion 114 such that the groove 114 a is sunken relative to the lowest portion of the sole portion 114.

According to aspects of the disclosure, the groove 114 a will correspond to, or match, the shape of the mass ring 201. For example, as seen in FIG. 4, the groove 114 a may be generally circular or oval shaped. As seen in FIG. 4, the mass ring 201 is configured to be engaged with the groove 114 a wherein the outer sides of the mass ring 201 (on both the inner circumference and the outer circumference) may contact and abut the ridges formed in the sole portion 114 by the groove 114 a. Further, as seen in FIG. 4, when the mass ring 201 is engaged with the groove 114 a, a portion of the sole portion 114 of the golf club head body 102 may extend through the opening in the center of mass ring 201.

Further, according to some aspects of the disclosure the mass ring 201 may, at least partially, extend around the perimeter of the sole portion 114. For example, as seen in FIG. 4, the mass ring 201 extends around the rear of the sole portion 114 and along the heel and toe sides of the sole portion 114. Further, as seen in FIG. 4, the section of the mass ring 201 which is opposite the section engaged with the rear of the sole portion 114, extends from the heel side to the toe side parallel to the ball striking face 108. Therefore, it can be seen that in this embodiment the mass ring 201 does not extend completely around the perimeter of the sole portion 114. However, in other embodiments, the mass ring 201 may extend completely around the perimeter of the sole portion 114. For example, the embodiment show in FIG. 5 shows such an embodiment wherein the mass ring 201 may extend completely around the perimeter of the sole portion 114.

According to some aspects of the disclosure, mass ring 201 may be sized so that its diameter extends substantially across the golf club head 102 from the toe end portion 116 to the heel end portion 118. However, in other embodiments the diameter may be smaller. For example, according to aspects of the disclosure, the mass ring 201 may have a diameter of between: 2.5-12.5 cm, 5.0-10.0 cm, and 7.0-8.0 cm. Further, according to aspects of the disclosure, the mass ring 201 may have a circular length between: 10-50 cm, 15.0-25.0 cm, 20.0-40.0 cm, and 30.0-35.0 cm. Additionally, the mass ring 201 may have a thickness between 0.25-2.0 cm, 0.5-1.75 cm, 0.75-1.5 cm, and 1.0-1.25 cm. It is noted that the thickness of the mass ring 201 is not necessarily uniform throughout. Instead, in some embodiments, the thickness of the mass ring may vary so that different sections of the mass ring 201 have different thicknesses.

The depth of the groove 114 a may be more than, equal to, or slightly less than the thickness of the mass ring 201. For example, the depth of the groove 114 a may be more than, equal to or slightly less than 0.25-2.0 cm, 0.5-1.75 cm, 0.75-1.5 cm, and 1.0-1.25 cm. As described above, since the shape of the groove 114 a may correspond to the shape of the mass ring 201, the dimensions of the groove 114 a may be similar to those described above regarding the mass ring 201. Hence, further specific discussion of the dimensions of the groove 114 a is omitted for the sake of brevity.

One advantage of configuring the sole portion 114 with a groove 114 a for receiving the mass ring 201 and, further, configuring the depth of the groove such that it is equal to, or slightly less than the thickness of the mass ring 201, is that when the mass ring 201 is engaged in the groove 114 a, the mass ring will not extend beyond the exterior of the remainder of the sole portion, so that the aerodynamics of the club head body 102 will not be affected during the golfer's swing. For example, both the thickness of the mass ring 201 and the depth of the groove 114 a can be configured so that when the mass ring 201 is engaged with the groove 114 a, the sole portion 114 is practically seamless and smooth.

Another advantage is that the configuration does not detract from the stability of the golf club at the address position (e.g., as shown in FIG. 1). In other words, with a practically seamless fit, the golf club head body 102 would sit just as it would if it were a conventional club head body without the interchangeable mass ring 201.

However, the above discussion is not intended to suggest that a groove 114 a is required. In fact, according to other aspects of the disclosure, the golf club head body 102 does not include a groove in the sole portion 114 of the golf club head body 102. For example, the mass ring 201 could be engaged with the sole portion 114 of a golf club head body 102 that does not include recesses or grooves configured to receive the mass ring 201. In other words, the mass ring 201 could be attached directly to the exterior of the wall of the sole portion 114.

It is noted that the mass ring 201 may have differing widths at different sections around the ring. For example, as seen in FIG. 5, according to aspects of the disclosure, a first section of the mass ring 201 may be wider than a second section of the mass ring 201. Of course, in other embodiments, the width of the mass ring 201 may be uniform throughout the mass ring 201. According to some aspects of the disclosure, a section of the mass ring 201 may have a width between 0.5-7.0 cm, 1.0-5.0 cm, 1.5-3.0 cm, and 2.0-2.5 cm.

The ruling bodies in the game of golf, such as the United States Golf Association (USGA) and The Royal and Ancient Golf Club of St. Andrews (R & A), do not allow portions of the golf club to be adjusted during the round of golf. See e.g., USGA Rules of Golf, Rule 4-2a. Therefore, to ensure the golf club does not violate such rules, regardless of how the interchangeable mass ring 201 is engaged with the sole portion 114, the interchangeable mass ring 201 should be held stationary by being locked into a particular position during a round of golf

According to aspects of this disclosure, the interchangeable mass ring 201 may be secured to the sole portion 114 of the golf club head body 102 in a variety of ways. For example, the sole portion 114 (e.g., the groove 114 a) and the mass ring 201 may include corresponding holes for receiving threaded fasteners. Therefore, threaded fasteners, such as screws, may be inserted which would secure the interchangeable mass ring 201 to the sole portion 114. Of course, other mechanical connectors such as retaining elements, snap fit features, etc. may be used. In some embodiments a tool may be used to attach and/or release the interchangeable mass ring 201 from the sole portion 114 of the club head body 102. For example, the above described configuration may require a screwdriver to tighten the screw into the holes of the sole portion 114 and interchangeable mass ring 201 to ensure the interchangeable mass ring 201 is locked into position. It is further noted that while some mechanical connectors have been described above, this is not to imply that mechanical connectors must be used. On the contrary, as long as the interchangeable mass ring 201 and the golf club head 102 can be engaged securely to one another and also easily releasable from one another, such means are considered within the spirit of this disclosure.

According to some aspects of this disclosure, the mass ring may have different weighting characteristics than the other parts of the golf club head body 102. For example, the mass ring 201 may have a large specific gravity, density and weight. For example, the mass ring 201 may have a greater specific gravity and be denser and heavier than other parts of the golf club head 102. For example, the mass ring 201 may be partially, substantially or entirely made from a high density and heavy material, such as various metals (e.g., as lead, tungsten), alloys, etc. According to aspects of this disclosure, the mass ring 201 may be partially, substantially or entirely made from a polymer (e.g., a relatively flexible and deformable polymer), plastic, elastomer, etc. According to aspects of this disclosure, the mass ring 201 may have a mass between 5.0-70 grams, 20-60 grams, or 30-55 grams.

Further, according to some aspects of this disclosure, the mass ring 201 may have at least a first section that has a different weighting characteristic than a second section of the mass ring 201. For example, the mass ring 201 may include more mass/weight at particular sections throughout the mass ring 201 than in other sections of the mass ring 201. For example, the mass ring 201 may include additional weights 202 at particular positions throughout the mass ring 201. The weights 202 may have a greater specific gravity and be denser and heavier than other parts of the mass ring 201. Therefore, the weights 202 would further increase the weight of the mass ring 201 in that section. In other words, the mass ring 201 may be point loaded. FIG. 4 shows an illustrative embodiment of a point loaded mass ring 201 according to aspects of this invention. As seen in FIG. 4, the mass ring 201 may include three weights 202 along one section of the mass ring 201.

According to some aspects of the disclosure, the mass ring 201 can be interchangeable. In other words, the mass ring 201 may be configured to be disengaged and reengaged from the golf club head body 102 (e.g., relatively easily disengaged and reengaged). In some instances the mass ring 201 may be replaced with another mass ring 201 which may have different weighting characteristics. For example, as discussed above, mass ring 201 may be a point loaded wherein more weight is provided at one section of the mass ring 201 than the other sections. Therefore, by replacing a point loaded mass ring 201 with a mass ring that is uniformly weighted the center of gravity of the golf club head body 102 may be shifted in a particular direction.

In the embodiment depicted in FIG. 4, mass ring 201 is point loaded with the weights 202 being positioned in the rear side of the club head body 102. This configuration of the mass ring 201 causes more mass to be distributed toward the rear side of the golf club head body 102. Such a configuration can help a golfer obtain a higher trajectory or get the ball airborne. Therefore, a golfer who has a tendency to “duff” (i.e., hit the ball so that it skims along the ground rather than travel with an elevated loft through the air) may engage a mass ring 201 with such a configuration in order to compensate for and alleviate the effects of the “duff” For example, in accordance with this disclosure, when the mass ring 201 is engaged in such a way, the center of gravity of the club head may be shifted towards the rear side of the golf club head body 102 at least 0.5 cm from the geometric centerline running front to back, and in some examples, at least 1.25 cm, at least 2.0 cm, or even at least 2.5 cm. As a result of the shifted center of gravity, the golf club head body 102 can provide a higher trajectory to a golf ball struck by the golf club head.

Of course, the mass ring 201 may be configured with the weights 202 in other sections as well. For example, the mass ring 201 could be configured so that when it is engaged with the sole portion 114 of the golf club head body 102, the additional weights 202 are positioned in the heel side of the golf club head body 102. This configuration of the mass ring 201 causes more mass to be distributed toward the heel side of the golf club head body 102. Such a configuration can help slow the heel during a swing as compared with the toe of the golf club head which will allow a golfer to better square the club head during the swing, which may result in less “slice” (i.e., a straighter trajectory). Therefore, a golfer who has a tendency to “slice” may engage a mass ring 201 with such a configuration in order to compensate for and alleviate the effects of the slice. For example, in accordance with this disclosure, when the mass ring 201 is engaged in such a way, the center of gravity of the club head may be shifted towards the heel side of the golf club head body 102 at least 0.5 cm from the geometric centerline running front to back, and in some examples, at least 1.25 cm, at least 2.0 cm, or even at least 2.5 cm. As a result of the shifted center of gravity, the golf club head body 102 can provide a draw biased trajectory to a golf ball struck by the golf club head.

Conversely, the mass ring 201 could be configured so that when it is engaged with the sole portion 114 of the golf club head body 102, the additional weights 202 are positioned in the toe side of the golf club head body 102. This configuration of the mass ring 201 causes more mass to be distributed toward the toe side of the golf club head body 102. As described above, such a configuration can help slow the toe during a swing as compared with the heel of the golf club head body 102 which will allow a golfer to better square the golf club head during the swing, which may result in less of a “hook” (i.e., a straighter trajectory). Therefore, a golfer who has a tendency to “hook” may engage a mass ring 201 with such a configuration in order to compensate for and alleviate the effects of the hook. For example, in accordance with this disclosure, when the mass ring 201 is engaged in such a way, the center of gravity of the club head may be shifted towards the toe side of the golf club head body 102 at least 0.5 cm from the geometric centerline running front to back, and in some examples, at least 1.25 cm, at least 2.0 cm, or even at least 2.5 cm. As a result of the shifted center of gravity, the golf club head body 102 can provide a fade biased trajectory to a golf ball struck by the golf club head.

Also, the mass ring 201 could be configured so that when it is engaged with the sole portion 114 of the golf club head body 102, the additional weights 202 are positioned in or near the ball striking face side of the golf club head body 102. Such a configuration causes more mass to be distributed toward the ball striking face side 111 of the golf club head body 102. Therefore, such a configuration can provide a shot in which a golf ball will “run” or roll. For example, in accordance with this disclosure, when the mass ring 201 is engaged in such a way, the center of gravity of the club head may be shifted towards the ball striking face side of the golf club head body 102 at least 0.5 cm, and in some examples, at least 1.25 cm, at least 2.0 cm, or even at least 2.5 cm. As a result of the shifted center of gravity, the golf club head body 102 can provide a shot that will cause a golf ball to “run” or roll when it is struck by the golf club head.

According to some aspects of the disclosure, the mass ring 201 (and optionally the groove 114 a) is configured such that mass ring 201 can be disengaged, rotated (e.g., in a clockwise or counter clockwise direction) to a different orientation and reengaged. In the case of a point loaded mass ring 201, the weight could be shifted to the opposite side of the club head body 102 in order to redistribute the mass and weight of the golf club head body 102. For example, to modify a club head body with a point loaded mass ring 201 wherein the weights 202 are in the heel side (and, therefore, the golf club head body 102 has a draw bias) to a club with a fade bias wherein the weights 202 are in the toe side of the club head body, a golfer would merely have to disengage the point loaded mass ring 201 and rotate the point loaded mass ring 201 (e.g., rotate the mass ring 180°) and reengage it with the club head body 102. In other words, the mass ring 201 could be disengaged from a first orientation wherein the mass ring 201 is engaged with the golf club head body 102 such that a first section of the mass ring which includes the weights 202 is in the heel side of the golf club head body 102. The mass ring 201 could then be rotated from a first orientation to a second orientation, wherein upon rotating the mass ring 201, the first section of the mass ring 201 that was in the heel side in the first orientation would now be in the toe side once the mass ring 201 is reengaged with the golf club head body 102 in the second orientation. The mass ring 201 would then be reengaged with the groove 114 a in the second orientation.

It is noted that, of course, the interchangeable mass ring 201 does not have to be point loaded and, instead, the weight could be uniform around the mass ring 201. Therefore, the interchangeable mass ring 201 could be replaced with another mass ring 201 that, while still uniform, has different weighting characteristics (e.g., it is uniformly lighter or heavier).

The above features allow the mass and weight distribution of the golf club head body 102 to be easily altered. Therefore, it is understood that the interchangeable mass ring 201 can be used to fine tune the mass and weighting characteristics of the golf club head body 102 based on the particular tendencies of the golfer. Hence, the club head body 102 could be easily customized and fitted to the particular golfer and their particular swing tendencies.

Regardless of whether the mass ring 201 is point loaded or uniformly weighted, when the mass ring 201 is engaged with the sole portion 114 of the golf club head body 102, the center of gravity of the golf club head body 102 is lowered. For example, in accordance with this disclosure, when the mass ring 201 is positioned on the sole portion 114 of the golf club head body 102, the center of gravity of the golf club head body 102 may be shifted towards the sole of the golf club head body 102 at least 0.5 cm and, in some examples, at least 1.25 cm, at least 2.0 cm, or even at least 2.5 cm. As a result of the shifted center of gravity, this configuration of the golf club head body 102 can provide a higher trajectory to a golf ball struck by the golf club head.

Further, as discussed above, this configuration of positioning the mass ring 201 on the sole portion 114 of the golf club head body 102, redistributes more mass of the golf club head body 102 to the edge of the golf club head body 102. Therefore, the MOI of the golf club head body 102 is increased. The increased MOI provides a greater resistance to the golf club head body 102 twisting during an off center impact with the golf ball and, hence, provides greater forgiveness upon a mis-hit.

Therefore, the above described configuration of engaging the mass ring 201 on the sole portion 114 of the golf club head body 102 not only lowers the center of gravity of the golf club head body 102 which provides a higher trajectory and aids the golfer in getting the ball in the air, but also the above described configuration redistributes the mass of the golf club head body 102 so that the MOI of the golf club head body 102 is increased and the golf club head body 102 is more forgiving on mis-hits.

Of course, the mass ring 201 does not necessarily have to be positioned at the sole portion 114 of the golf club head body 102. In fact, according to aspects of this disclosure, the mass ring 201 may be positioned in other portions of the golf club head body 102. For example, as seen in FIG. 6, a mass ring 201 may be engaged with the exterior of the rear portion 110 of the golf club head body 102 wherein it encircles the rear portion 110 and engages both the crown portion 112 and sole portion 114 of the golf club head body 102.

As seen in FIG. 6, the mass ring 201 may be generally circular or oval shaped. However, the mass ring 201 could be formed in various other geometric shapes as well depending on the configuration of the golf club head (e.g., if the golf club head is more curved or square, etc.). Of course, the ring shape of mass ring 201 will provide an opening in the center of the mass ring 201.

According to some aspects of the disclosure, the exterior of the rear portion 110 may include a groove 110 a for receiving the mass ring 201. For example, FIG. 6 is an illustrative embodiment of such a golf club head body 102 and a mass ring 201 according to aspects of the disclosure. As seen in FIG. 6, the golf club head body 102 has a rear portion 110 with a groove 110 a according to aspects of this disclosure. As seen in FIG. 6, the groove 110 a may be a “cut-out” of the rear portion 110 along both the crown 112 portion and sole portion 114. In other words, the groove 110 a may recede from an outer surface of the rear portion 110 in a similar fashion as described above with regard to groove 114 a in FIG. 4.

According to aspects of the disclosure, the groove 110 a will match the shape of the mass ring 201. For example, as seen in FIG. 6, the groove 110 a may be generally circular or oval shaped. As seen in FIG. 6, the mass ring 201 engages with the groove 110 a wherein the outer sides of the mass ring 201 (on both the left and right sides) may contact and abut the ridges formed in the crown portion 112 and sole portion 114 by the groove 110 a. Further, as seen in FIG. 6, when the mass ring 201 is engaged with the groove 110 a, the rear portion 110 of the golf club head body 102 may extend through the opening in the center of mass ring 201.

Similarly to the above described embodiment, the depth of the groove 110 a may be more than, equal to, or slightly less than the thickness of the mass ring 201. One advantage of configuring the rear portion 110 with a groove 110 a for receiving the mass ring 201 and, further, engaging the mass ring 201 in the groove 110 a, is that the aerodynamics of the golf club head body 102 will not be affected during the golfer's swing. For example, both the thickness of the mass ring 201 and the depth of the groove 110 a can be configured so that when the mass ring 201 is engaged with the groove 110 a, the rear portion 110 is practically seamless and smooth.

However, as described above with regard to the above embodiment a groove 110 a is not required and, in fact, according to other aspects of disclosure, the golf club head body 102 does not include a groove 110 a in the rear portion 110 of the golf club head body 102. Instead, the mass ring 201 may be attached directly to the exterior of the wall of the rear portion 110.

Also, it is noted that many of the features of the mass ring 201 and groove 110 a of this embodiment are similar to the above described embodiments (e.g., different thickness and widths of the mass ring 201, point loading or uniform weighting characteristics around the mass ring 201, means of attachment, interchangeability, flipping or rotating of the mass ring to alter the weight distribution and center of gravity, etc). Therefore, for the sake of brevity such features will not be specifically reiterated here.

However, it is noted, that in the embodiment depicted in FIG. 6, mass ring 201 is positioned in the rear side 109 of the golf club head body 102. This configuration of the mass ring 201 causes more mass to be distributed toward the rear side 109 of the golf club head body 102. As described above, such a configuration can help a golfer obtain a higher trajectory or get the ball airborne. For example, in accordance with this disclosure, when the mass ring 201 is engaged in such a way, the center of gravity of the club head may be shifted towards the rear side 109 of the golf club head body 102 at least 0.5 cm from the geometric centerline running front to back, and in some examples, at least 1.25 cm, at least 2.0 cm, or even at least 2.5 cm. As a result of the shifted center of gravity, this configuration of the golf club head body 102 can provide a higher trajectory to a golf ball struck by the golf club head.

Further, is noted that if the mass ring 201 is point loaded and configured to be engaged with the golf club head body 102 such that the additional weight 202 is positioned at the sole portion 114 of the golf club head body 102, the center of gravity will also be lowered. For example, in such a configuration, the center of gravity of the golf club head body 102 may be shifted towards the sole of the golf club head body 102 at least 0.5 cm and, in some examples, at least 1.25 cm, at least 2.0 cm, or even at least 2.5 cm. As a result of the shifted center of gravity, this configuration of the golf club head body 102 can provide a higher trajectory to a golf ball struck by the golf club head.

Further, this configuration of positioning the mass ring 201 on the rear portion 110 of the golf club head body 102, redistributes more mass of the golf club head body 102 to the edge of the golf club head body 102. Therefore, as discussed above, the MOI of the golf club head body 102 is increased. This increased MOI provides a greater resistance to the golf club head body 102 twisting during and off center impact with the golf ball and, hence, provides greater forgiveness upon a mis-hit.

Therefore, the above described configuration of engaging the mass ring 201 on the rear portion 110 of the golf club head body 102 not only moves the center of gravity of the golf club head body 102 towards the rear of the club head body which provides a higher trajectory and aids the golfer in getting the ball in the air, but also the above described configuration redistributes the mass of the golf club head body 102 so that the MOI of the golf club head is increased and the golf club head is more forgiving on mis-hits.

Of course, as described above, the interchangeable mass ring 201 may be positioned in a location other than shown in the above embodiments.

Golf professionals are known to work with golfers to assist them in improving their golf game including their swing and associated play by analyzing the golfer's tendencies, providing instruction and recommendation regarding modifications to their swing and also in recommending various equipment including selection of clubs. Further, a golf professional for a certain golf manufacturer may offer a selection of features for which the golfer may select either alone, or with the assistance of the golf professional. Among the features that vary from golf club to golf club are various weighting characteristics of the golf club head. Each golfer may have a swing tendency that varies from other golfers. Accordingly, golfers may desire and benefit from an individualized fitting of a golf club such that the golfer's swing characteristics and swing tendencies may be noted and accounted for. In a fitting process, a golfer may have his or her swing analyzed by a professional either visually or by using any of various measuring and analysis devices known in the art.

FIGS. 7A-7C illustratively depict one manner of fitting a golf club 100 including the weighting characteristics of the golf club head body 102. As is known, a golfer 10 may perform a number of swings in front of one or more golf professionals or golf club fitters. The movements including the golf swing may be viewed, recorded, and/or measured by a measuring device including a videographic device like a digital video camera. FIGS. 7A and 7B illustrate top plan and rear views respectively of a golfer swinging a golf club and hitting golf balls in an illustrative fitting station 1000. The fitting station 1000 may have any of a number of arrangements and features. The fitting station 1000 shown in FIGS. 7A-7C is an indoor fitting station. However, fitting station 1000 may be indoor or outdoor and may be located at a driving range or other practice facilities, at a golf course including in or near a pro shop and various other locations as are known. The fitting station 1000 may include a hitting mat 1010, especially when the fitting station is an indoor station or when the station is part of a driving range. Here, the indoor fitting station 1000 also includes a net 1030 that a golfer 10 may hit the ball into in performing his or her shots, practice swings and swings in front of a golf professional or golf club fitter. The net 1030 permits the fitting to be done in a more limited space such as indoors, in a pro shop or in a driving range with limited land available. Behind the net 1030 may be a background 1040 or other structures that may make the golfer 10 feel as if he or she is on the golf course. Also, while not specifically depicted, the background may house or protect a further measuring device(s) including velocity or force sensors, videographic devices and other devices that may be utilized in the fitting of the golfer 10.

The ball travel of a golfer's shot may be monitored by watching an entire ball flight at a fitting station on a driving range that possesses sufficient space for the ball to travel until it comes to a natural stopping point/lie. Also, a golfer may also hit in a confined spaced monitored by a digital video camera or other computing devices that can determine the travel path based upon initial characteristics of the shot including velocity, trajectory, spin etc. Measuring devices may be used to further understand the swing path and related tendencies of a golfer. In one example configuration, a golfer's swing may be filmed using a digital video camera device 1060. In particular the golfer's swing may be filmed from a toe end view such that the golfer 10 has a stance square to and facing the camera. In another configuration, the golfer's swing may alternatively or additionally be filmed by a measuring device positioned at a position such as the position where measuring device 1061 is illustratively shown. By filming the golfer's swing from square orientations such as the rear and toe end, the video may be compared to images and swing paths performed and recorded by a golfer having preferred mechanics as shown in FIG. 7C.

Among the devices and tests that may be used to monitor the swing path, contact orientation and related characteristics of a golfer swing are video recording, radar tracking including Doppler radar technology, motion detection devices, speed radar devices, ball flight tracking devices and monitoring systems and similar golf swing analysis devices as are known in the art. These measuring devices may be positioned as illustrative measuring devices 1060, 1061. These devices may also be positioned in front of the golfer 10 such that the golfer is hitting at the measuring device or on the heel end side of the golfer behind the golfer's back. Even further, measuring devices 1060 and 1061 may be placed overhead or practically anywhere such that the measuring devices 1060 and 1061 can record data such as video images of the golfer's movements or track and record data or characteristics associated with the portions of the golf club or ball movement such as velocity, direction, orientation, and other characteristics as are known. Other devices focused at determining the golf club's orientation during the swing and in particular the orientation of the golf club through the hitting zone when the golf club head strikes the golf ball may be utilized. These devices may be the same or similar devices as the videographic, radar or other motion tracking devices or the devices may be as simple as lie board devices which depict where a bottom surface of the golf club contacts the ground and the direction of movement and orientation of the club through the hitting zone. Also basic tape devices placed over the hitting surface 1020 of a golf club head may be used to provide data regarding the portion of the hitting surface 1020 where the golf ball is being hit to determine whether the ball is being hit in a desired spot on the club face (e.g., center) or off-center such that the swing or club may need adjustment to optimize results.

After a sufficient number of swings and “practice” or “sample” shots have been made to provide a desired sampling of shots to provide for a reliable fitting, the golf and/or fitting professionals can use the data collected to recommend particular mass and weighting characteristics for a golf club head body 102 (including the positioning of the one or more moveable weight members with the golf club head body 102) that will help the golfer 10 hit a golf ball in an intended and desired direction and/or with an intended and desired flight path. Among the characteristics collected or measured may include swing path data, trajectory, orientation of the golf club on impact, ball spin, ball flight and physical dimensions and ergonomic characteristics of the golfer, to name just a few. The analysis of the swings including swing patterns can be used to determine a desired swing path, tendencies of the golfer's swing, and changes to the golfer's current swing path such that the specific changes required may be more visibly noticeable. The mass and weighting characteristics may be determined and shown such that an analysis (e.g., computer analysis) can be performed to determine whether a particular mass ring 201 (and its particular weighting characteristics) and the way it engages with the golf club head body 102 is appropriate as maximizing the performance of a golfer with particular swing tendencies.

FIG. 7C illustrates a display 1050 depicting two respective swing characteristics outputs 1051, 1052 illustratively depicting two swings of golfers in videographic form such as digital video. In one arrangement the displayed swing 1051 may be a videographic image of preferred swing of a professional golfer or other golfer including a “virtual golfer” with preferred swing mechanics. On the right, the golf swing 1052 may be an actual swing of a golfer 10 currently being analyzed in the fitting station 1000. Through the split screen comparison on display 1050, a golfer 10 may be analyzed and fitted for particular golf club features such as visual swing indicators, shaft characteristics, and alignment aides and other features to facilitate a golfer swinging in a preferred manner to achieve preferred performance. For example, backswing paths 1055A, 1055B of the golfers may be compared during the swings 1051, 1052. Likewise, the orientations of the golf club head 1056A, 1056B, the golfers' arm and hand positions 1057A, 1057B, and the head positions 1058A, 1058B may be compared visual. Other comparisons and analysis may be performed as is known. While the display 1050 here illustrates videographic information relating to the golfers' swings, the display 1050 may be utilized during other aspects of the analysis including output of various other characteristics utilized in fitting the golfer 10. Further, as shown in FIG. 7B the display 1050 may also be used to enhance the fitting experience and may be visible to the golfer 10 during the fitting process. However, various configurations of outputs can be used to perform a swing analysis and provide output data relating to the golfer's swing to the golfer or the golf professional.

Therefore, using the above described fitting processes, the determination of a particular mass ring 201 (and its particular weighting characteristics) along with how the mass ring 201 is engaged with the golf club head body 102 can be particularly utilized to adjust and control mass and weighting characteristics of the golf club head body 102 to customize the golf club head body 102 to fit particular swing types or a golfer's tendencies. For example, the above described fitting processes could be used in conjunction with a method for determining which mass ring 201 to employ and how best to engage the mass ring 201 with a golf club head body 102 in order to provide an intended and desired trajectory for the golf ball. The method includes determining a characteristic of a golfer's swing based upon a swing of the golf club using a measuring device. The method further includes determining a desired ball trajectory. The method further includes selecting a particular mass ring 201 and how that mass ring 201 should be engaged with the golf club head body 102 based upon the determined swing characteristic and the desired ball trajectory. The method further includes engaging the mass ring with the golf club head body 102 at a position that will provide the desired ball trajectory.

Conclusion

Aspects of the present invention are described above and in the accompanying drawings with reference to a variety of example structures, features, elements, and combinations of structures, features, and elements. The purpose served by the disclosure, however, is to provide examples of the various features and concepts related to the invention, not to limit the scope of the invention. One skilled in the relevant art will recognize that numerous variations and modifications may be made to the embodiments described above without departing from the scope of the present invention, as defined by the appended claims.

For example, the dimensions and/or other characteristics of a golf club head structure according to examples of this disclosure may vary significantly without departing from the disclosure. For example, any wood type club head may be provided including, for example: wood type hybrid clubs, fairway woods, drivers, etc.

Additionally, the various features and concepts described above in conjunction with FIGS. 1 through 7 may be used individually and/or in any combination or subcombination without departing from this disclosure. 

I claim:
 1. A golf club head comprising: a wood type golf club head body including a ball striking face portion, a rear portion opposite the ball striking face, a crown portion and a sole portion; and a mass ring configured to engage with the rear portion of the golf club head body, wherein the mass ring is configured to encircle the rear portion and is configured to engage both the crown portion and the sole portion of the golf club head body, wherein the mass ring increases a moment of inertia of the golf club head body, wherein the mass ring includes an opening in a center of the mass ring, wherein a portion of the rear portion of the golf club head body extends through the opening in the center of mass ring, and wherein the mass ring is engageable in at least a first orientation where a center of gravity of the golf club head body is located at a first position, and a second orientation where the center of gravity of the golf club head body is located at a second position spaced from the first position.
 2. The golf club head according to claim 1, wherein the mass ring forms a portion of the exterior of the golf club head body.
 3. The golf club head according to claim 2, wherein the rear portion of the golf club head body includes a groove that receives the mass ring, wherein the shape of the groove corresponds to the shape of the mass ring.
 4. The golf club head according to claim 3, wherein the mass ring is engaged with the groove wherein outer sides of the mass ring contact and abut ridges formed in the sole portion and the crown portion by the groove.
 5. The golf club head according to claim 4, wherein a depth of the groove is equal to or slightly greater than a thickness of the mass ring such that the mass ring does not extend beyond an exterior of a remainder of the rear portion.
 6. The golf club head according to claim 1, wherein the mass ring is interchangeable with a second mass ring with different weighting characteristics.
 7. The golf club head according to claim 1, wherein the mass ring is point loaded such that at least a first section of the mass ring has a different weighting characteristic than a second section of the mass ring.
 8. The golf club head according to claim 7, wherein the mass ring is engagable with the groove in at least a first orientation where a center of gravity of the golf club head body is located at a first position, and a second orientation where the center of gravity of the golf club head body is located at a second position spaced from the first position
 9. A golf club head comprising: a wood type golf club head body having a ball striking face portion and a rear portion opposite the ball striking face portion; and a mass ring engaged with the golf club head body, wherein the mass ring is configured to engage the rear portion the golf club head body, wherein the mass ring is configured to encircle the rear portion and is configured to engage both a crown portion and a sole portion of the golf club head body, wherein the rear portion of the club head body includes a groove configured to receive the mass ring, wherein the shape of the groove corresponds to the shape of the mass ring, and wherein the mass ring is engageable with the groove in at least a first orientation where a center of gravity of the golf club head body is located at a first position, and a second orientation where the center of gravity of the golf club head body is located at a second position spaced from the first position.
 10. The golf club head according to claim 9, wherein the mass ring engages the groove wherein outer sides of the mass ring contact and abut ridges formed in the crown portion and the sole portion by the groove, and a portion of the rear portion of the golf club head body extends through an opening in a center of the mass ring.
 11. The golf club head according to claim 10, wherein a depth of the groove is equal to or slightly greater than a thickness of the mass ring such that the mass ring does not extend beyond an exterior of a remainder of the rear portion when the mass ring is engaged with the rear portion.
 12. The golf club head according to claim 9, wherein the mass ring is interchangeable with a second mass ring with different weighting characteristics.
 13. The golf club head according to claim 9, wherein the mass ring is point loaded such that at least a first section of the mass ring has a different weighting characteristic than a second section of the mass ring.
 14. A method of altering a center of gravity of the golf club head that includes a golf club head body with a ball striking face portion and a rear portion opposite the ball striking face portion, and a point loaded removable mass ring engaged with an exterior of the rear portion, the method comprising: disengaging the mass ring from a first orientation which provides the center of gravity of the golf club head at a first position; and reengaging the mass ring with the golf club head body in a second orientation which provides the center of gravity of the golf club head body at a second position.
 15. The method according to claim 14, wherein the mass ring includes at least a first section of the mass ring and a second section of the mass ring wherein the first and second sections have different weighting characteristics.
 16. The method according to claim 15, wherein the rear portion of the golf club head body includes a groove for receiving the mass ring in different orientations and the groove and the mass ring are configured to allow the mass ring to be disengaged from the first orientation, rotated to the second orientation, and reengaged in the second orientation.
 17. The method according to claim 16, wherein the center of gravity moves from a crown portion of the golf club head body to a sole portion of the golf club head body or vice versa when rotating the mass ring and reengaging the mass ring with the golf club head body in the second orientation.
 18. A kit comprising: a golf club head body having a ball striking face portion and a rear portion opposite the ball striking face portion; and an interchangeable mass ring configured to be engaged with an exterior of the rear portion of the golf club head body, wherein the mass ring is point loaded such that the mass ring has increased weight in at least one location relative to other locations on the mass ring; wherein the interchangeable mass ring includes an opening in a center of the mass ring; wherein a portion of the exterior of the rear portion of the club head body extends through the opening in the center of mass ring when engaged with the golf club head body; wherein the interchangeable mass ring increases a moment of inertia of the golf club head body when engaged with the golf club head body; wherein the interchangeable mass ring is engageable in at least a first orientation where a center of gravity of the golf club head body is located at a first position, and a second orientation where the center of gravity of the golf club head body is located at a second position spaced from the first position.
 19. The kit of claim 18, further comprising: a plurality of interchangeable mass rings wherein at least two of the interchangeable mass rings have different weighting characteristics. 